/*******************************************************************************

ATTENTION, this is an altered version of the xhtml_gen library, specifically tailored to libwebconf's needs please refer to the original library

Tree Container Library: Generic container library to store data in tree-like structures.
Copyright (c) 2006  Mitchel Haas

This software is provided 'as-is', without any express or implied warranty. 
In no event will the author be held liable for any damages arising from 
the use of this software.

Permission is granted to anyone to use this software for any purpose, 
including commercial applications, and to alter it and redistribute it freely, 
subject to the following restrictions:

1.	The origin of this software must not be misrepresented; 
	you must not claim that you wrote the original software. 
	If you use this software in a product, an acknowledgment in the product 
	documentation would be appreciated but is not required.

2.	Altered source versions must be plainly marked as such, 
	and must not be misrepresented as being the original software.

3.	The above copyright notice and this permission notice may not be removed 
	or altered from any source distribution.

For complete documentation on this library, see http://www.datasoftsolutions.net
Email questions, comments or suggestions to mhaas@datasoftsolutions.net
*******************************************************************************/
#pragma once
#include <set>
#include <stack>
#include <queue>
#include <algorithm>

// stored_type:			type stored in container
// tree_type:			one of three tree types derived from this base
// container_type:		type of contain to hold children (can be set or multiset)

template< typename stored_type, typename tree_type,  typename container_type >
class basic_tree 
{
	public:
	// typedefs
		typedef basic_tree<stored_type, tree_type, container_type> basic_tree_type;
		typedef stored_type* (*tClone_fcn) (const stored_type&);

	protected:
	// constructors/destructor
		basic_tree() : pData(0), pParent_node(0)  {}
		explicit basic_tree(const stored_type& stored_obj);
		basic_tree(const basic_tree_type& rhs);  // copy constructor
		~basic_tree();

	public:
	// child iterator definitions
		class const_iterator : public std::iterator<std::bidirectional_iterator_tag, tree_type*>
		{
			public:
			// typedefs
				typedef class basic_tree<stored_type, tree_type, container_type> basic_tree_type;

			// constructors/destructor
				const_iterator() {}
				explicit const_iterator(typename container_type::const_iterator it_, const basic_tree_type* pParent_) : it(it_), pIt_parent(pParent_) {}
				virtual ~const_iterator() {}

			// overloaded operators
				friend bool operator != ( const const_iterator& lhs, const const_iterator& rhs )  { return !(lhs == rhs); }
				friend bool operator == ( const const_iterator& lhs, const const_iterator& rhs )  { return lhs.pIt_parent == rhs.pIt_parent && lhs.it == rhs.it; }

				const tree_type& operator*() const { return  **it; }
				const tree_type* operator->() const { return *it; }

				const_iterator& operator ++() { ++it; return *this; }
				const_iterator operator ++(int) { const_iterator old(*this); ++*this; return old; }
				const_iterator& operator --() { --it; return *this; }
				const_iterator operator --(int) { const_iterator old(*this); --*this; return old; }

			// public interface
				const tree_type* node() { return *it; }

			// data
			protected:
				typename container_type::const_iterator it;
				const basic_tree_type* pIt_parent;
		};

		class iterator : public const_iterator
		{
		protected:
				using const_iterator::it;
		public:
			// constructors/destructor
				iterator() {}
				explicit iterator(typename container_type::iterator it_, basic_tree_type* pParent_) : const_iterator(it_, pParent_) {}
				virtual ~iterator() {}

			// overloaded operators
				tree_type& operator*() { return **it; }
				tree_type* operator->() { return *it; }
				iterator& operator ++() { ++it;  return *this; }
				iterator operator ++(int) { iterator old(*this); ++*this; return old; }
				iterator& operator --() { --it; return *this; }
				iterator operator --(int) { iterator old(*this); --*this; return old; }

			// public interface
				tree_type* node() { return *it; }
		};
		typedef iterator basic_tree_iterator;  // needed for descendant constructor specification problems

		// descendent tree iterator definitions

		class const_pre_order_iterator : public std::iterator<std::bidirectional_iterator_tag, tree_type*>
		{
		public:
			// constructors/destructor
			const_pre_order_iterator() {}
			virtual ~const_pre_order_iterator() {}
		protected:
			explicit const_pre_order_iterator(const basic_tree_type* pTop_node_) { it = pTop_node_->begin(); pTop_node = pTop_node_; }
			explicit const_pre_order_iterator(const_iterator& it_) : it(it_) {}

		public:
			// overloaded operators
			friend bool operator != ( const const_pre_order_iterator& lhs, const const_pre_order_iterator& rhs ) { return lhs.it != rhs.it; }
			friend bool operator == ( const const_pre_order_iterator& lhs, const const_pre_order_iterator& rhs ) { return lhs.it == rhs.it; }
			const_pre_order_iterator& operator ++() { return incr(); }
			const_pre_order_iterator operator ++(int) { const_pre_order_iterator old(*this); ++*this; return old; }
			const_pre_order_iterator& operator --() { return decr(); }
			const_pre_order_iterator operator --(int) { const_pre_order_iterator old(*this); --*this; return old; }

			// public interface
			const tree_type& operator*() const { return  it.operator *(); }
			const tree_type* operator->() const { return it.operator ->(); }
			const tree_type* node() { return it.node(); }
			friend class basic_tree<stored_type, tree_type, container_type>;
		private:
			const_pre_order_iterator& incr()
			{
				if ( !it->empty() ) { // any children?
					node_stack.push(it); // yes. push current pos
					it = node()->begin(); // and goto first child
				} else {
					++it; // no children. incr to next sibling if present
					// while stack not empty and no next sibling
					while ( !node_stack.empty() && it == (node_stack.top())->end() ) {
						it = node_stack.top(); // pop parent
						node_stack.pop();
						++it; // and see if it's got a next sibling
					}
				}
				return *this; 
			}
			const_pre_order_iterator& decr()
			{
				if ( it == pTop_node->end() ) { // at end?
					// yes. need to set up stack to state just before end
					rit = pTop_node->children.rbegin(); // going backwards
					if ( rit != pTop_node->children.rend() ) { // insure there's children
						if ( !(*rit)->empty() ) { // last node have children?
							do {  // find the last child of this node
								++rit; // incr reverse iter..
								it = const_iterator(rit.base(), node()); // ..to convert to fwd iter correctly
								node_stack.push(it); // push parents on the way down
								rit = node()->children.rbegin(); // get last child again
							} while ( !(*rit)->empty() ); // while last child has children
							++rit; // incr reverse iter
							it = const_iterator(rit.base(), node()); // to convert to forward iter correctly
						}
					}
				} else { // not at end.
					if ( it != node()->parent()->begin() ) { // is this first sibling?
						--it; // no.  ok to decr to next sibling
						if (!it->empty()) { // children present?
							do { // yes.  get deepest last child
								node_stack.push(it); // first push current 
								it = const_iterator(node()->children.end(), node());
								--it;  // then go to last child
							} while ( !it->empty() ); // while children present
						}
					} else { // first sibling
						it = node_stack.top(); // just need to goto parent
						node_stack.pop();
					}
				}
				return *this;
			}

			// data
		protected:
			std::stack<const_iterator> node_stack;   
			const basic_tree_type* pTop_node;
			const_iterator it;
			typename container_type::const_reverse_iterator rit;
		};
		
		class pre_order_iterator : public const_pre_order_iterator
		{
		public:
			using const_pre_order_iterator::it;
			// constructors/destructor
			pre_order_iterator() {}
			virtual ~pre_order_iterator() {}
		protected:
			explicit pre_order_iterator( basic_tree_type* pTop_node_) : const_pre_order_iterator(pTop_node_) {}
			explicit pre_order_iterator(basic_tree_iterator& it_) : const_pre_order_iterator(it_) {}

		public:
			// overloaded operators
			pre_order_iterator& operator ++() { ++(*static_cast<const_pre_order_iterator*>(this)); return *this; }
			pre_order_iterator operator ++(int) { pre_order_iterator old(*this); ++*this; return old; }
			pre_order_iterator& operator --() { --(*static_cast<const_pre_order_iterator*>(this)); return *this; }
			pre_order_iterator operator --(int) { pre_order_iterator old(*this); --*this; return old; }

			// public interface
			tree_type& operator*() { return  const_cast<tree_type&>(it.operator *()); }
			tree_type* operator->() { return const_cast<tree_type*>(it.operator ->()); }
			tree_type* node() { return const_cast<tree_type*>(it.node()); }
			friend class basic_tree<stored_type, tree_type, container_type>;
		};

		class const_post_order_iterator : public std::iterator<std::bidirectional_iterator_tag, tree_type*>
		{
		public:
			// constructors/destructor
			const_post_order_iterator() {}
			virtual ~const_post_order_iterator() {}
		protected:
			explicit const_post_order_iterator(const basic_tree_type* pTop_node_) { init(pTop_node_); }
			explicit const_post_order_iterator(const_iterator& it_) : it(it_) {}

		public:
			// overloaded operators
			friend bool operator != ( const const_post_order_iterator& lhs, const const_post_order_iterator& rhs ) { return lhs.it != rhs.it; }
			friend bool operator == ( const const_post_order_iterator& lhs, const const_post_order_iterator& rhs ) { return lhs.it == rhs.it; }
			const_post_order_iterator& operator ++() { return incr(); }
			const_post_order_iterator operator ++(int) { const_post_order_iterator old(*this); ++*this; return old; }
			const_post_order_iterator& operator --() { return decr(); }
			const_post_order_iterator operator --(int) { const_post_order_iterator old(*this); --*this; return old; }

			// public interface
			const tree_type& operator*() const { return  it.operator *(); }
			const tree_type* operator->() const { return it.operator ->(); }
			const tree_type* node() { return it.node(); }
			friend class basic_tree<stored_type, tree_type, container_type>;

		private:
			void init(const basic_tree_type* pTop_node_)
			{
				pTop_node = pTop_node_; // save invoked node
				it = pTop_node->begin(); // goto first child
				if ( !it->empty() ) { // have children of it's own?
					do {  // goto deepest first child, while pushing parents
						node_stack.push(it);
						it = node()->begin();
					} while ( !it->empty() );
				}
			}

			const_post_order_iterator& incr()
			{
				const_iterator it_end = node()->parent()->end(); // end sibling
				++it; // advance to next sibling, if present
				if ( it != it_end && !it->empty() ) { // next sibling present, and has children?
					do {  // goto deepest first child while pushing parents
						node_stack.push(it);
						it = node()->begin();
					} while ( !it->empty() );
				} else { // it is past last sibling, or it has no children
					// if valid it and it has no childrent, were done
					if ( !node_stack.empty() && it == (node_stack.top())->end() ) {
						// it is past last sibling, and pushed parents exist.  move back up to parent
						it = node_stack.top();
						node_stack.pop();
					}
				}
				return *this;
			}

			const_post_order_iterator& decr()
			{
				if ( it == pTop_node->end() ) { // at end?
					typename container_type::const_reverse_iterator rit = pTop_node->children.rbegin();
					++rit;
					it = const_iterator(rit.base(), pTop_node); // goto last sibling of top node
				} else { // not at end
					if ( !node()->empty() ) { // children present?
						typename container_type::const_reverse_iterator rit = node()->children.rbegin();
						node_stack.push(it);
						++rit; // push parent and go to last child
						it = const_iterator(rit.base(), node());
					} else { // no children present
						if ( it != node()->parent()->begin() ) { // at first sibling?
							--it; // no.  just goto prev sibling
						} else { // at first sibling. work our way up until not first sibling
							while ( !node_stack.empty() && it == node_stack.top()->begin())
							{
								it = node_stack.top();
								node_stack.pop();
							}
							--it; // then goto prev sibling
						}
					}
				}
				return *this;
			}

			// data
		protected:
			std::stack<const_iterator> node_stack;   
			const basic_tree_type* pTop_node;
			const_iterator it;
			typename container_type::const_reverse_iterator rit;
		};


		class post_order_iterator : public const_post_order_iterator
		{
		public:
			using const_post_order_iterator::it;
			// constructors/destructor
			post_order_iterator() {}
			virtual ~post_order_iterator() {}
		protected:
			explicit post_order_iterator(basic_tree_type* pTop_node_) : const_post_order_iterator(pTop_node_) { }
			explicit post_order_iterator(basic_tree_iterator& it_) : const_post_order_iterator(it_) {}

		public:
			// overloaded operators
			post_order_iterator& operator ++() { ++(*static_cast<const_post_order_iterator*>(this)); return *this; }
			post_order_iterator operator ++(int) { post_order_iterator old(*this); ++*this; return old; }
			post_order_iterator& operator --() { --(*static_cast<const_post_order_iterator*>(this)); return *this; }
			post_order_iterator operator --(int) { post_order_iterator old(*this); --*this; return old; }

			// public interface
			tree_type& operator*() { return  const_cast<tree_type&>(it.operator *()); }
			tree_type* operator->() { return const_cast<tree_type*>(it.operator ->()); }
			tree_type* node() { return const_cast<tree_type*>(it.node()); }
			friend class basic_tree<stored_type, tree_type, container_type>;

		};

		class const_level_order_iterator : public std::iterator<std::forward_iterator_tag, tree_type*>
		{
		public:
			// constructors/destructor
			const_level_order_iterator() {}
			virtual ~const_level_order_iterator() {}
		protected:
			explicit const_level_order_iterator(const basic_tree_type* pTop_node_) : pTop_node(pTop_node_), node_depth(0) { it = pTop_node_->begin(); }
			explicit const_level_order_iterator(const_iterator& it_) : it(it_) {}

		public:
			// overloaded operators
			friend bool operator != (const const_level_order_iterator& lhs, const const_level_order_iterator& rhs) { return lhs.it != rhs.it; }
			friend bool operator == (const const_level_order_iterator& lhs, const const_level_order_iterator& rhs) { return lhs.it == rhs.it; }
			const_level_order_iterator& operator ++() { return incr(); }
			const_level_order_iterator operator ++(int) { const_level_order_iterator old(*this); ++*this; return old; }
			// declare, but don't define decr operators
			const_level_order_iterator& operator --();
			const_level_order_iterator operator --(int);

			// public interface
			const tree_type& operator*() const { return  it.operator *(); }
			const tree_type* operator->() const { return it.operator ->(); }
			int depth() const { return node_depth; }
			const tree_type* node() { return it.node(); }
			friend class basic_tree<stored_type, tree_type, container_type>;
		private:
			const_level_order_iterator& incr()
			{
				const_iterator it_end = node()->parent()->end(); 
				node_queue.push(it); // push current pos node in queue
				++it;  // and goto next sibling if present

				if ( it == it_end ) { // past last sibling?  If not, we're done.
					while ( !node_queue.empty() ) { // yes. Insure queue not empty
						it = node_queue.front(); // pull pos off queue
						node_queue.pop(); // this should be the start pos of level just traversed
						if ( !it->empty() ) { // have children?
							it = node()->begin(); // yes. descend to start of next level
							++node_depth;
							break;
						} else if ( node_queue.empty() ) { // no children.  is queue empty?
							it = pTop_node->end(); // yes. at end
							return *this;
						}
					} 
				}
				return *this;
			}

			// data
		protected:
			const_iterator it;
			std::queue<const_iterator> node_queue;
			const basic_tree_type* pTop_node;
			int node_depth;
		};

		class level_order_iterator : public const_level_order_iterator
		{
		public:
			using const_level_order_iterator::it;
			// constructors/destructor
			level_order_iterator() {}
			virtual ~level_order_iterator() {}
		protected:
			explicit level_order_iterator(basic_tree_type* pTop_node_) : const_level_order_iterator(pTop_node_) { }
			explicit level_order_iterator(basic_tree_iterator& it_) : const_level_order_iterator(it_) {}
		
		public:
			// overloaded operators
			level_order_iterator& operator ++() { ++(*static_cast<const_level_order_iterator*>(this)); return *this; }
			level_order_iterator operator ++(int) { level_order_iterator old(*this); ++*this; return old; }

			// public interface
			tree_type& operator*() { return  const_cast<tree_type&>(it.operator *()); }
			tree_type* operator->() { return const_cast<tree_type*>(it.operator ->()); }
			tree_type* node() { return const_cast<tree_type*>(it.node()); }
			friend class basic_tree<stored_type, tree_type, container_type>;
		};

	// public interface
		bool is_root() const { return pParent_node == 0; }
		tree_type* parent() const { return pParent_node; }
		bool empty() const { return children.empty(); }
		int size() const { return static_cast<int>(children.size()); }

		const_iterator begin() const { return const_iterator(children.begin(), this); }
		const_iterator end() const { return const_iterator(children.end(), this); }
		iterator begin() { return iterator(children.begin(), this); }
		iterator end() { return iterator(children.end(), this); }
		post_order_iterator post_order_begin() { post_order_iterator it(this); return it; }
		post_order_iterator post_order_end() { iterator it = end(); return post_order_iterator(it); }
		const_post_order_iterator post_order_begin() const { const_post_order_iterator it(this); return it; }
		const_post_order_iterator post_order_end() const { const_iterator it = end(); return const_post_order_iterator(it); }
		pre_order_iterator pre_order_begin() { pre_order_iterator it(this); return it; }
		pre_order_iterator pre_order_end() { iterator it = end(); return pre_order_iterator(it); }
		const_pre_order_iterator pre_order_begin() const { const_pre_order_iterator it(this); return it; }
		const_pre_order_iterator pre_order_end() const { const_iterator it = end(); return const_pre_order_iterator(it); }
		level_order_iterator level_order_begin() { level_order_iterator it(this); return it; }
		level_order_iterator level_order_end() { iterator it = end(); return level_order_iterator(it); }
		const_level_order_iterator level_order_begin() const { const_level_order_iterator it(this); return it; }
		const_level_order_iterator level_order_end() const { const_iterator it = end();  return const_level_order_iterator(it); }
		const stored_type* get() const { return pData; }
		stored_type* get() { return pData; }
		void set(const stored_type& stored_obj);
		void for_each( void (*pFcn)(stored_type&) );
		template<typename T> void for_each( T& func_ob )
		{
			func_ob(*get()); // call operator() on root
			pre_order_iterator it = pre_order_begin(), it_end = pre_order_end();
			for ( ; it != it_end; ++it )  // call operator() on all descendants
				func_ob(*it.node()->get());
		}
		static void set_clone(const tClone_fcn& fcn) { pClone_fcn = fcn; }
		void clear();
		void erase(iterator it);
	protected:
		void set_parent(tree_type* pParent) { pParent_node = pParent; }
		basic_tree_type& operator = (const basic_tree_type& rhs); // assignment operator
		iterator insert( const stored_type& stored_obj, tree_type* parent );
		iterator insert(stored_type* pStored_obj, tree_type* parent);
		iterator insert(const tree_type& tree_obj, tree_type* parent);
		void set(const tree_type& tree_obj, tree_type* parent);
		void allocate_stored_type(stored_type*& stored_ptr, const stored_type& stored_obj) 
			{ stored_ptr = stored_type_allocator.allocate(1,0); stored_type_allocator.construct(stored_ptr, stored_obj); }
		void deallocate_stored_type(stored_type* stored_ptr) 
			{ stored_type_allocator.destroy(stored_ptr); stored_type_allocator.deallocate(stored_ptr, 1); }
		void allocate_tree_type(tree_type*& tree_ptr, const tree_type& tree_obj)
			{ tree_ptr = tree_type_allocator.allocate(1,0); tree_type_allocator.construct(tree_ptr, tree_obj); }
		void deallocate_tree_type(tree_type* tree_ptr)
			{ tree_type_allocator.destroy(tree_ptr); tree_type_allocator.deallocate(tree_ptr, 1); }
		
	// data
	protected:
		container_type children;
	private:
		stored_type* pData;   // data accessor
		mutable tree_type* pParent_node;
		static tClone_fcn pClone_fcn;
		std::allocator<stored_type> stored_type_allocator;
		std::allocator<tree_type> tree_type_allocator;
};

#include "basic_tree.inl"
